This proposal is designed to expand the base of knowledge related to the psychophysical, clinical, and psychophysiological variables that affect the reaction to laboratory and pathological pain. Aim #1, a long-range study comparing migraine headache sufferers to normals, will be conducted to provide information about the differences in pain judgments made by these populations. It is also planned to investigate the effects of several non-pharmaceutical treatments on the pain responses of the migraine headache sufferers. Aim #2 continues the work related to the effect of the manipulation of large and small fiber activity on pain perception. An attempt will also be made to record averaged A variation and C fiber activity in order to compare neutral and behavioral pain responses. Aim #3 extends our research on the psychophysical evaluation of pain descriptor terms as pain response measures. Aim #4 is aimed at developing and testing the methodology and measures that can be used to build an individual pain perception profile that can be utilized by clinicians.